The present invention relates to a motor-driven compressor.
Japanese Laid-Open Patent Publication No. 11-294365 discloses a motor-driven compressor of the prior art. The motor-driven compressor includes a compressor mechanism, which compresses a refrigerant, and a motor mechanism, which actuates the compressor mechanism. The motor-driven compressor includes an inner housing, which accommodates the compressor mechanism and the motor mechanism in a sealed state, and an outer housing, which accommodates the inner housing.
A spring, which supports the inner housing, is arranged in the outer housing of the motor-driven compressor. Thixotropic fluid is filled in a void formed between the outer housing and the inner housing. The outer housing includes a mounting portion that allows for mounting to another member.
The spring and thixotropic fluid function to suppress the transmission of vibration and noise from the compressor mechanism and motor mechanism to the exterior of the motor-driven compressor.
In this prior art motor-driven compressor, the heat of the high-temperature and high-pressure refrigerant compressed by the compressor mechanism is transmitted via the inner housing and the spring to the outer housing and released to the exterior or absorbed via the inner housing by the thixotropic fluid. Accordingly, there is a tendency for the heat of the refrigerant to be easily decreased. Thus, for example, when the motor-driven compressor is used in a heat pump, the heating performance of the heat pump becomes insufficient.